Pruning-knife.



F. A. FRUMVILLER.

PRUNING KNIFE.

APPLIUATION Hum mm. a, 1909.

978,574. Patented Dec. 13,1910.

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UNITED STATES PATENT OFFICE.

FRANK A. FRUMVILLER, 0F DETROIT, MICHIGAN.

PRUNING-KNIFE.

To all whom it may concern:

Be it known that I, FRANK A. Farm- VILLER, a citizen of the UnitedStates, and a resident of Detroit, in the county of WVayne and State ofMichigan, have invented a new and Improved Pruning-Knife, of which thefollowing is a full, clear, and exact description.

Among the principal objects which the present invention has in view are:to provide an implement of the character specified wherein the pull onthe implement is converted into a cutting force; to provide an implementof the character specified wherein the wear incident to the cuttingstrain is provided for; to provide a construction wherein the shreddingof the bark from limbs being severed is overcome; to provide aconstruction wherein the cutting strain introduced upon the blade isbalanced; and to provide a construction which is light, durable andsimple in arrangement and operation.

One embodiment of the present invention is disclosed in the structureillustrated in the accompanying drawings, in which like characters ofreference denote corresponding parts in all the views, and in whichFigure 1 is a side view of a pruning knife constructed and arranged inaccordance with the present invention, and shown in its closed position.Fig. 2 is a detail view in perspective of the bill hook of the presentpruner; Fig. 3 is a detail view in perspective of the knife; Fig. 4 is afragmentary detail view in vertical section of the bill hook, thesection being taken through the pivot line of the knife and the billhook; and Fig. 5 is a detail view in perspective of the anchorage forthe resetting spring.

Heretofore the ordinary pruning knife, in the majority of instances,consists of a single stationary blade upon which is mounted in wipingcontact a pivoted cutting blade, the action being similar to that knownas a shearing action. The cutting has principally depended upon thealinemcnt or Wipe of the cutting edges and this has been maintained by asuitable pivot. The natural wear has resulted in the loosening of thecutting blade upon the pivot or in the bending of the pivot underoperation. In every instance the cutting edges of the two blades flareto a greater or less extent, permitting the shredded end of the limbbeing cut, or the bark of the same, to extend between the Specificationof Letters Patent.

Application filed September 3, 1909.

Patented Dec. 13, 1910.

Serial No. 516,047.

cutting blades forming a hanging member for the limb being severed. Thispartial failure to sever the limb has caused a great deal of trouble inthat the bark constituting the hanging member is difiicult to engagebetween the cutting members. It is to over come such an objection that Ihave provided the present head, consisting of a bill hook which consistsof two pieces 8 and 9. The two pieces 8 and 9 of the bill hook are giventhe ordinary crook shape common to imple ments of this character and aremaintained in their separated relation by rivet bolts 10, 10. The member8 forming the bill hook is provided with a stationary shear or cuttingedge 11 against which the squared side of the knife sweeps. The member 9of the bill hook is raised slightly above the cutting edge of the member8 and is provided with a lower edge more square in form, against whichthe limb or twig rests while being cut. The cutting edge 11 isreinforced by being thickened in cross section, as shown in thedrawings, and provided with a beveled sharpened side. Both parts arebossed outwardly to form elongated bearings 12 for pivot bolts 13. Themember 9 is extended to the rear to form an offset 14: which operates asa guide for the knife in its initial cutting position. Both members areprovided with reinforcing projections 15 and annular half-flanges 16.The half-flanges 16 are set out from half-tubes 17 of which they form anintegral part. The halftubes 17 are adapted to extend within the upperend of the casing 18 and to be therein held by a suitable screw bolt 19which extends through perforations 20 formed in the said half-tubes 17,forming in such relation a rigid structure.

The blade 21 is secured in the bill hook by being inserted between themembers 8 and 9 so that a perforation 22 formed in the said blade alineswith the perforations in the bearings 12. In such position the pivotbolt 1. is introduced, passing through both the perforation in thebearings 12 and in the blade 21. The blade 21 differs from the ordinaryblade in that it is provided with extensions 23 and 24. The extension 23is set out from the rear end of said blade and is perforated to receivethe upper end of a spring 25. The extension 24- is provided to receive ahook end 26 of a pull rod 27. Both the pull rod 27 and the spring 25 areso disposed with reference to the blade 21 that when the parts areassembledthe median line of the said rod and spring coincides with themedian line of the blade 21 whereby the pull strain exerted by the saidrod 27 and spring 25 is directed evenly upon the pivot bolt 13,producing no canting strain on the said blade.

It is by means of the pull rod 27 that the blade 21 is swung in suchmanner as to sever thelimb or twig for which the pruner is constructed.To accomplish this the lower end of the said rod is hooked about a pin28 and extended through ears 29 set out from a collar 30. The collar 30is provided with outwardly turned edges whereby the same slides morefreely on a handle 31. The collar 30 is normally held in position by abolt or cotter pin 32 which is attached to the loose end of a chain 33provided to prevent the said pin from becoming detached and possiblylost. The chain 33 is sufficiently long to permit the introduction ofthe pin 32 within perforations 34 extended through the lower end of thecasing 18 and the handle 31, in which position certain actions transpireto be hereinafter explained.

When the collar 30 is fixedly mounted in position upon the handle 31 bymeans of the bolt 32, and the rod 27 is connected thereto, the pruningimplement is in condition to operate. This operation is as follows: Inits retracted position the casing 18 and bill hook connected therewithrests upon the collar 30. In this position the rod 27 elevates theextension 24 of the blade 21 so that the cutting edge of the blade isretracted within the members 8 and 9, as shown in Fig. 1 of thedrawings. The bill hook having been placed through the branch it isdesired to sever the handle 31 is pulled downward. The bill hook andcasing 18 being held by the branch, the pulling strain is exertedthrough the medium of the collar 30 and the rod 27 directly upon theblade 21. This pull rotates the said blade about the pivot bolt 13 andcloses the blade 21 upon the extended ends of the bill hook and insertsthe same between the members 8 and 9 thereof. In this manner theinterposed branch or twig is severed.

The spring 25 operates to reset the blade 21 in the open position. Itaccomplishes this by being attached to the rod 27 by means of a collar35 secured upon the said rod. The exertion of the spring 25 is such thatit compels the rod, spring and blade to assume the position shown inFig.l of the drawings, for the reason that it is in that position that thesaid spring is extended least. In the positions shown in Figs. 2 and 3of the drawings the spring is extended, from which position they aredrawn from the direction of the spring. The attachment between thespring 25 and the collar 35 is by means of a hook 363.

The cutting operation has been above described. When the spring 25 isincorporated as an element in the implement the blade 21 is reset to thecutting position shown in Fig. 1 of the drawings whenever the strain onthe handle 31 is released.

hen employing this implement in the operation of cutting small twigs orbranches not having resistance sutficient to maintain their positionunder the pull of the handle when cutting, I prepare the implement byextending the casing 18 sufliciently to aline the perforations 34: withthe perforations provided in the handle 31, and then inserting the bolt32 through the perforations 34- and handle 31, holding the said casingand handle as a single rigid member. The pin 32 is withdrawn fromengagement with the handle 31, and to it is attached a flexible cord orcable 37 as illustrated in Fig. 3 of the drawings, this beingsufficiently stout to give the desired cutting pull on the rod 27 toclose the blade 21 upon the interposed twig or branch. In this latteroperation the method difi'ers only in that when the bill hook 8, 9 isplaced over a branch or twig instead of pulling upon the handle 31 thisis maintained in fixed position while the pull is exerted upon the cordor cable 37,

thus operating to swing the blade 21 upon its pivot bolt 13 and closethe cutting edge of said blade against the members 8, 9. In thisoperation, the double membered bill book, it will be observed, supportsor holds in preferred position for cutting the interposed twig orbranch, the member 9 supporting the free or to be severed portion of thesaid branch or twig, while the member 8 serves as a stationary memberfor the operation of the cutting blade 21.

It will be observed that throughout the operations above described thepull of both the rods 27 and spring 25 in their respective actions uponthe blade 21 have been central to the pivot bearing of the said blade.This produces an even wear upon the said bearing. It also produces aconstruction where, in the event of a wear, the blade would still berotated in a central manner.

The collar 35 may be secured upon the rod 27 in any suitable manner,that preferred by me consisting in locating the same in pre-- ferredposition and then contracting the section or point thereof to takepositive hold upon the said rod. One method of doing this would be tostrike the collar with a prick punch or common nail set. At any time, by

driving lightly the collar 35 may be placed hook-like members eachrovided with a laterally extended boss, said bosses being perforated inline to form bearings, one of said hook-like members having formed onthe inner curved edge thereof a cutting edge, the other of said membershaving a squared inner curved edge; a guide extension formed on themember having the said squared edge, said guide extension projected atthe side of said extended bosses opposite to the extension of the saidhook-like member; a pivot member extended through said perforationsformed in said bosses; a guiding blade pivotally mounted on said pivotmember and

